The invention relates to a steam iron having a shell, a sole plate, a heating element, a water reservoir, a steam chamber, a steam needle for the inflow of water from the water reservoir into the steam chamber, and a pump mechanism comprising a pump piston, a piston chamber in which the piston can move, inlet and outlet ports for the piston chamber, a return spring and a control element for moving the piston in the opposite direction so as to pump water from the pump reservoir.
Such a steam iron is disclosed in U.S. Pat. No. 3,165,843. This prior art steam iron has a pump mechanism by means of which a quantity of water can rapidly be pumped into the steam chamber so as to obtain a high steam production. The object thereof is to enable appropriately smooth ironing of very crinkled materials. The piston of the pump mechanism is rigidly secured to the steam needle. The piston chamber is positioned at the lowest point in the bottom of the water reservoir. The steam needle has such a profile that it combines a normal controllable steam function with a function to obtain extra steam. This means that the requirements as regards accuracy, particularly for the steam needle, are extra high, more specifically as regards a properly controllable steam production during the normal steaming operation.